1. Field of the Invention
The invention relates to a numeral setting apparatus for setting numerals such as a copy magnification and the like.
2. Related Background Art
Hitherto, in various kinds of electronic apparatuses, an operating system having various constructions is used to input various control data.
In the case of inputting quantity or numeric data, there is a method whereby a potentiometer is operated by a lever, a volume knob, or the like. In recent years, since a microprocessor or the like is used as a controller to control the apparatus, there is frequently used a method whereby numerals are directly input by using a ten-key, a method whereby up/down keys are used and an input numeral is continuously increased or decreased for a period of time when the up or down key is depressed, or the like.
The method of directly inputting numerals by using the ten-key or the method using the up/down keys is also used, for instance, to set a magnification, a number of copies, a density, or the like in a copying apparatus which can perform a zooming operation.
The method using the ten-key or the up/down keys has an advantage such that construction is simple and the apparatus is cheap because there is no need to use a lever, an A/D converting process, and the like in a control system of a microprocessor or the like.
In the conventional apparatus, however, in the case of deciding a numeral by using the up/down keys, there are the following drawbacks. The operation system of the copying apparatus will now be described as an example hereinbelow.
Although a copy magnification variable range differs depending on a copying apparatus, there is a tendency such that a variable range becomes wider at present in many copying apparatuses. For instance, there is a copying apparatus having a variable range from 50 to 400% in which the magnification can be set on a 1% unit basis.
In the case-of the apparatus of the type such that the magnification is changed by 1% each time the up/down key is depressed once, the up/down key must be depressed many times to set a desired magnification.
In the case of the type such that the magnification is continuously changed by continuously depressing the up/down key, the magnification must be slowly changed to accurately set a desired magnification because there are 350 kinds of magnifications.
In the case of slowly changing the magnification, however, it takes a very long time and operating efficiency is bad. For instance, assuming that the magnification has been changed by 0.5 second per data, it takes about three minutes to completely change the magnification, so that such a method is not practical.
On the other hand, in the case of the type such that a changing speed of the magnification is increased by about ten times to thereby quickly set a desired magnification when the up/down key is continuously depressed for a few seconds, the changing speed is so fast that it is difficult to stop the depression of the up/down key at a position corresponding to the desired magnification. There is a situation such that the magnification exceeds the desired magnification and the magnification must be often returned to the desired magnification by operating the up/down key in the opposite direction. Thus, there is a drawback such that it is troublesome to accurately set the desired magnification.
The above problems also similarly occur in the application fields such that the number of copies, an area to perform an edition, and a density in a copying apparatus are set or that the up/down keys are operated in a service mode to input operating condition data of a machine main body, and the like. Even in apparatuses other than the copying apparatus, the apparatus using an interface by using the similar up/down keys has problems similar to those mentioned above.